The present invention relates generally to containment basins and in particularly to a containment basin for a portable storage tank to contain liquid spillage from the tank.
A variety of liquid materials are supplied from the material producer to the end user in transportable storage tanks such as the reusable container disclosed in patent application Ser. No. 07/871,284, filed Apr. 20, 1992, commonly assigned and hereby incorporated by reference. This container includes a lower discharge fitting and valve for use in removing the liquid contents. In many instances, the lower discharge valve will be connected directly to the equipment using the supplied liquid material. Once connected, the discharge valve is opened and the liquid contents are used as needed. When a tank is used that does not have a lower outlet, the top opening of the tank is opened and a pump is used to remove the tank contents.
During use, it is not uncommon for a certain amount of spillage to occur from the tank during the process of connecting or disconnecting the tank. Faulty valves and fittings, etc., can also result in leakage. Depending upon the liquid material, environmental or workplace safety regulations may require that the spilled liquid be contained for proper disposal. Furthermore, good housekeeping may require containment of the liquid spillage to prevent the spilled liquid from covering the floor of the workplace. To accomplish this, portable tanks are placed in containment basins having raised side walls to surround the tank and contain any spilled liquid. To be effective, the containment basins must be capable of containing 100% of the tank contents. As a result, the basin side walls are of a substantial height in order to minimize the floor space covered by the basin.
One difficulty with such a containment basin is that the tank must be raised over the basin side wall or lowered into a basin formed in a recess in the floor. With a storage tank of any significant size, a forklift or other mechanical hoist is required to lift the tank into and out of the basin.
Accordingly, it is an object of the present invention to provide a containment which overcomes the above disadvantage to enable a portable tank to be moved into the containment basin or removed from the basin on a wheeled dolly, without lifting of the tank.
The containment basin of the present invention includes a bottom panel and an upstanding wall extending generally upwardly from the periphery of the bottom panel to an open upper end. The basin bottom panel and side wall thus enclose a volume of space open from above. The upstanding wall includes a pair of spaced opposing end portions and a pair of spaced opposing side portions adjacent to the end portions. The basin further includes a hinge portion between the bottom panel and one of the end portions for enabling the end portion to be rotated between an upstanding operative position and a lowered position aligned with the surrounding floor whereby a portable storage tank can be moved onto the bottom panel and removed from the bottom panel with a wheeled dolly, eliminating the need for lifting of the storage tank. A seal is provided between the movable end portion and the two adjacent side portions of the upstanding wall to prevent leakage of liquid during use of the containment basin.
In a preferred embodiment, the seal is in the form of a flexible fan member attached to the side and end portions of the wall which is expandable in an accordion like fashion as the end portion is rotated from the upstanding operative position to the lowered position.
Further objects, features and advantages of the invention will become apparent from a consideration of the following description and the appended claims when taken in connection with the accompanying drawings.